When you are faced with an anal cancer diagnosis, nutrition can be an important part of your journey. Eating a well-balanced diet before, during, and after cancer treatment can help you feel better, maintain your strength, and speed your recovery.

  • Maintain a healthy weight. Treatments such as chemotherapy, radiation, and surgery for anal cancer can often contribute to unintentional weight loss. It’s important to avoid excess weight loss during treatment as poor nutrition status can cause decrease the body’s ability to fight infection.
  • Eat small, frequent meals throughout the day. Eating frequent small meals will ensure your body is getting enough calories, protein, and nutrients to tolerate treatment. Smaller meals may also help to reduce treatment-related side effects such as nausea. Try eating 5-6 small meals or “mini” meals about every three hours.
  • Choose protein-rich foods. Protein helps the body to repair cells and tissues.  It also helps your immune system recover from illness. Include a source of lean protein at all meals and snacks.  Good sources of lean protein include:
    • Lean meats such as chicken, fish, or turkey
    • Eggs
    • Low fat dairy products such as milk, yogurt, and cheese or dairy substitutes
    • Nuts and nut butters
    • Beans
    • Soy foods
  • Include whole grain foods. Whole grain foods provide a good source of carbohydrate and fiber, which help keep your energy levels up. You may be asked by your doctor to avoid whole-grains and high-fiber foods while an ostomy is in place because these foods can increase output. Good sources of whole grain foods include:
    • Oatmeal
    • Whole wheat breads
    • Brown rice
    • Whole grain pastas
  • Eat a variety of fruits and vegetables every day. Fruits and vegetables offer the body antioxidants, which can help fight against cancer. Choose a variety of colorful fruits and vegetables to get the greatest benefit. Aim to eat a minimum of 5 servings of whole fruits and vegetables daily.
  • Choose sources of healthy fat. Avoid fried, greasy, and fatty foods, Choose baked, broiled, or grilled foods instead. Healthy fats include:
    • Olive oil
    • Avocados
    • Nuts
    • Seeds
  • Limit sweets and added sugars. Foods high in added sugars like desserts and sweets provide little nutritional benefit and often take the place of other foods that are better for you.

  • Stay hydrated. Drinking enough fluids during cancer treatment is important for preventing dehydration. Aim to drink 64 ounces of fluid daily. Avoid drinking large amounts of caffeinated beverages. Too much caffeine can lead to dehydration.
  • Be observant of changes in bowel habits. Anal cancer and treatments can often lead to changes in bowel habits including diarrhea, constipation, bloating, and gas. It is important for you to communicate with your healthcare team any changes in your bowel habits. Changes in your diet or medications may be necessary to manage these side effects.
  • Practice good food safety. Wash your hands often while preparing food. Use different knives and cutting boards for raw meat and raw vegetables. Be sure to cook all foods to their proper temperature and refrigerate leftovers right away.
  • Talk to your healthcare team before taking any vitamins or supplements.  Some medications and cancer treatments may interact with vitamins and supplements.  Choose food first as the main source for nutrients.
  • Drink alcohol in moderation, if at all.  Alcohol may contribute to dehydration, can lower the abilities of your immune system, and provides no beneficial nutrients.
  • Most importantly, know that your cancer journey is unique to you and your treatment. You may experience side effects that affect your ability to follow these suggestions. If you are struggling with any side effects, such as loss of appetite, nausea, diarrhea, vomiting, or any other nutrition concerns, your needs may be different. A registered dietitian can suggest nutrition guidelines that will be appropriate for your cancer journey.

Some types of cancer and cancer treatments may cause stomach discomfort and diarrhea. Your doctor may recommend that you follow a low-residue, or low-fiber, diet. A low-fiber diet reduces the amount and frequency of bowel movements, therefore reducing irritation to your digestive tract. Your healthcare team may also recommend a low-fiber diet if you have a colostomy or ileostomy, or recent intestinal surgery.

Suggestions for a low-residue, low-fiber diet are listed below. When reading nutrition labels on packaged foods, look for foods that contain fewer than 2 grams of dietary fiber per serving. Ask for a referral to a registered dietitian (RD) to help you find out how much fiber you should be consuming.


  • Raw, undercooked fruits and vegetables
  • Fruits and vegetables with seeds, skins, or hulls Cooked greens or spinach
  • Peas and corn
  • Berries
  • Dried fruits
  • Juices with pulp
  • Prune juice
  • Tough meats with gristle
  • Fried meat, poultry, or fish
  • Sushi
  • Dried beans, peas, or lentils
  • Sausage, bacon, or hot dogs
  • Chunky nut butters
  • Whole grains, such as whole wheat bread, brown rice, quinoa, barley, oatmeal, and popcorn

You may also want to avoid these gas-forming vegetables: beets, broccoli, Brussels sprouts, cabbage, lima beans, mushrooms, okra, onions, parsnips, peppers, and potato skins.


  • Canned or well-cooked fruits and vegetables
  • Low-fat milk (if lactose intolerant, choose lactose-free)*
  • Yogurt without added granola, fruit, nuts, or seeds*
  • Soymilk, rice milk, or almond milk*
  • Sherbet*
  • Tender, well-cooked meat, poultry, pork, or fish
  • Eggs
  • Smooth nut butters
  • Tofu
  • White bread, pasta, or rice
  • Cream of Wheat
  • Grits
  • Cold and hot cereals made from refined white flour
  • Pancakes and waffles made with refined white flour
  • Oils, butter, cream cheese, margarine, mayonnaise
*Although milk does not contain fiber, it can leave a residue in your intestines, leading to diarrhea and discomfort. If you can tolerate milk, limit milk products to no more than 2 cups per day. If you are lactose intolerant, try using lactose-free products.

What about dessert?

Choose desserts without whole grains, seeds, nuts, raisins, or coconut. Desserts can be high in sugar, which can cause diarrhea to worsen. Limit yourself to small portions of these treats. Some examples include sugar cookies, popsicles, angel food cake, Italian ice, and gelatin.

For a meal plan to meet your specific needs and food habits, ask your healthcare team for a referral to a registered dietitian (RD) who works with cancer patients. If you struggle with your food choices or don’t have enough energy, an RD can help you develop a healthy meal plan.

The immune system is weakened during all types of cancer treatment. Unfortunately, chemotherapy medications are not able to tell the difference between healthy cells and cancer cells. For this reason, perfectly healthy red and white blood cells are damaged or killed during treatment and shortly thereafter. The result of this is that body is not as good at fighting illness and infection. A common term used to refer to a very low neutrophil (white blood cell) count is neutropenia. Paying special attention to food safety during cancer treatment to reduce the risk of exposure to food borne illness may also be referred to a neutropenic diet. The following are some simple tips to reduce exposure and avoid unnecessary infection and/or illness during the time the immune system is compromised.


  • Wash hands often and thoroughly especially before handling any food as well as after. Be sure to wash hands with warm water and soap for at least 20 seconds. Pay special attention to finger nails and the backs of the hands.
  • Keep raw and cooked foods separate. Do not reuse any utensils, cutting boards, plates, dishes, etc. once they have been touched by raw meat or eggs. Utensils, cutting boards, plates, dishes, etc. that have been used for preparing raw meats or eggs should be washed in hot, soapy water. It is best to keep separate cutting boards for meat and fruits/vegetables. Have an extra clean cutting board available for additional preparation as well.
  • When shopping for and storing raw meats, keep them away from other foods and cover the packages with extra plastic wrap or use plastic bags. This will prevent any liquids from leaking onto other foods or surfaces. Store meats and eggs toward the bottom of the refrigerator to prevent any dripping on other foods below.

Cook Food Thoroughly

  • Avoid raw meat such as sushi, undercooked eggs (make sure eggs are at least “over easy” and not “sunny side up”), and other meats that have not been cooked to a proper internal temperature.
  • Cook all eggs until both the white and the yolk are firm.
  • Use a meat thermometer to make sure that all meats are cooked to the proper internal temperature prior to eating.

    Foods To Avoid

    • Raw or undercooked meats
    • Unpasteurized milk and juices
    • Soft cheeses made with unpasteurized milk such as feta, blue cheese, Roquefort, Stilton, brie, or Farmer’s cheese
    • Processed meats such as luncheon meats as well as anything else from a deli counter
    • Refrigerated meat spreads or paté
    • Smoked fish or precooked shrimp or crab meat
    • Sprouts such as bean sprouts, alfalfa sprouts, or broccoli sprouts
    • Pre-cut fresh fruit and vegetables. Buy them whole, wash, and cut them yourself using proper sanitary techniques as outlined above.
    • Unwashed fresh fruits and vegetables
    • Unroasted or raw nuts and seeds
    • Raw tofu or tempeh
    • Food from salad bars of buffets
    • “Fresh” salad dressings, salsas, sauces, etc. sold in the refrigerated section of the grocery store.
    • Raw apple cider
    • Raw honey
    • Unrefrigerated cream filled pastries

    The guidelines above were created with those who have severely weakened immune systems in mind. Consult your physician or health care team for regular updates on your blood counts and the status of your immune system.